Header only retrieval in php via curl

curl, header, php

Solution

You are passing $header to `curl_getinfo()`. It should be `$curl` (the curl handle). You can get just the `filetime` by passing `CURLINFO_FILETIME` as the second parameter to `curl_getinfo()`. (Often the `filetime` is unavailable, in which case it will be reported as -1).

Your class seems to be wasteful, though, throwing away a lot of information that could be useful. Here's another way it might be done:

class URIInfo 
{
    public $info;
    public $header;
    private $url;

    public function __construct($url)
    {
        $this->url = $url;
        $this->setData();
    }

    public function setData() 
    {
        $curl = curl_init();
        curl_setopt($curl, CURLOPT_URL, $this->url);
        curl_setopt($curl, CURLOPT_FILETIME, true);
        curl_setopt($curl, CURLOPT_NOBODY, true);
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($curl, CURLOPT_HEADER, true);
        $this->header = curl_exec($curl);
        $this->info = curl_getinfo($curl);
        curl_close($curl);
    }

    public function getFiletime() 
    {
        return $this->info['filetime'];
    }

    // Other functions can be added to retrieve other information.
}

$uri_info = new URIInfo('http://www.codinghorror.com/blog/');
$filetime = $uri_info->getFiletime();
if ($filetime != -1) {
    echo date('Y-m-d H:i:s', $filetime);
} else {
    echo 'filetime not available';
}

Yes, the load will be lighter on the server, since it's only returning only the HTTP header (responding, after all, to a `HEAD` request). How much lighter will vary greatly.

Problem

Original source